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Science in Sport GO Isotonic gel pineapple



High performing gel with carbohydrates for energy and fluid for hydration; tastes good, slips down easily, and is fair value

At every product is thoroughly tested for as long as it takes to get a proper insight into how well it works. Our reviewers are experienced cyclists that we trust to be objective. While we strive to ensure that opinions expressed are backed up by facts, reviews are by their nature an informed opinion, not a definitive verdict. We don't intentionally try to break anything (except locks) but we do try to look for weak points in any design. The overall score is not just an average of the other scores: it reflects both a product's function and value – with value determined by how a product compares with items of similar spec, quality, and price.

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Science in Sport (SiS) is a British company that's been in the sports nutrition business for over two decades, with a large range of products for cyclists and other athletes. The flagship Go Isotonic Energy Gel is available in various flavours, including the new pink grapefruit flavour, and the pineapple flavour tested here. These gels slip down easily and provide a good mix of fluid and carbohydrate to keep you going — and they taste good too.

There are numerous energy gels on the market these days, and the choice can be bewildering. The SiS Go Isotonic Gels are designed to combine carbohydrate and water in a specific ratio (22g of carb in a 60ml gel), so you don't need to drink from your bottle to help swallow the gel. More importantly, say SIS, this mix of carb and fluid makes Go Isotonic gels more effective as a source of energy.

As well as water, the main ingredient is maltodextrin (from maize) to provide the carbohydrate, plus various flavourings, preservatives and a sweetener. And that's about it.

Despite — or perhaps because of — the relatively short ingredients list, on test rides I found these SIS gels very effective, with a refreshing taste. They are easy to consume on the go, and easy on the stomach, and on that basis I'd recommend them as worth a try.

It's worth noting the size of these gels, however, in relation to the amount of carb they provide. As a rule of thumb, most cyclists have enough energy reserves to keep going for about two to three hours of hard riding before needing to top up, and after that most of us need about 50 to 90g of carb per hour – depending on the type of carb, the type of riding, our own physiology and other variable factors.

On that basis, the 22g of carb in an SiS Go gel will keep you going for about 20 minutes to half an hour, which means you'll need to carry quite a few if you're doing an 100-mile sportive and don't want to rely on the feed stations. In contrast, gels from some other brands are high on carb and low on fluid (for example, ZipVit ZV7 gels contain 51g of carb in a 60ml gel), although this latter option is more 'chewy' and definitely needs to be washed down with a drink.

Which option you go for will be a matter of personal choice and depend on the type of cycling you do. If you're a rider that prefers to reduce unnecessary weight in the jersey pockets — especially on long sportives when you'll be carrying food for several hours — you may go for gels that are high on carb, and get your liquid from the bottles on your bike. On the other hand, if you want to ensure you stay hydrated and you don't mind extra bulk in your back pocket, or you just prefer a lighter texture in your mouth, then gels such as these Go Isotonic Gels might be the option for you.

On price, Go Isotonic Gels cost £1.29 each, with a box of 30 costing £38.70 from the SiS website (and less than £30 from some online discount stores). This compares to gels from other manufacturers such as the aforementioned ZipVit's ZV7 (a box of 24 x 60g gels costs £30 to £40, depending on supplier) or Mulebar's Kick (a box of 24 x 37g gels costs around £35), making the SiS gels fair value.


High performing gel with carbohydrates for energy and fluid for hydration; tastes good, slips down easily, and is fair value test report

Make and model: Science in Sport GO Isotonic Energy - Pineapple flavour

Size tested: 8 sent

Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?

This product is an energy gel, designed for consumption during a training ride, race or sportive. The SiS website says 'The SiS GO Isotonic Gel was the world's first isotonic gel effectively delivering an easily digestible and quick supply of carbohydrate for energy during exercise. SiS GO Gels are designed to be consumed without water meaning that you can ensure rapid delivery of carbohydrate to your muscles without the feelings of being bloated that can sometimes occur with over-drinking '

Tell us some more about the technical aspects of the product?

The SiS website includes the following nutritional information: Each gel provides 368kj/87kcal. The only energy source is carb. These gels contain no protein, fibre or fat, and just 0.01g of salt.

The full list of ingredients is: Water, Maltodextrin (produced from partial hydrolyses of a special variety of Maize), Gelling Agents (Gellan Gum, Xanthan Gum ), Natural Flavouring, Acidity Regulators (Citric Acid, Sodium Citrate), Preservatives (Sodium Benzoate, Potassium Sorbate), Sweetener (Acesulfame K), Sodium Chloride, Antioxidant (Ascorbic Acid)

The gels are suitable for vegans.

Rate the product for performance:

Performance is very good, in that these gels do exactly what they're supposed to do: provide energy and fluid. And they taste good too. However, some cyclists might find these gels simply too large for the amount of carbs they provide.

Rate the product for weight, if applicable:

Each gel weighs about 68g, and provides 22g of carb. That's about 40g of water (plus the minor ingredients and the wrapper). Some cyclists might prefer less water and more carbs. It's a personal thing.

Rate the product for value:

Value is fair, when compared against similar products, but for most bike riders it won't be matter of price. It'll be a matter of personal preference on the taste and texture of the gel and it's effectiveness as an energy source. As with all energy products, try it in training, and it works for you stick with it for races and other serious outings. If it doesn't work for you, try something else.

Tell us what you particularly liked about the product

Flavour, texture.

Tell us what you particularly disliked about the product

Generally, I prefer gels with a higher carb content, and to carry less in my back pocket, but that's a personal thing.

Did you enjoy using the product? Yes.

Would you consider buying the product? Yes.

Would you recommend the product to a friend? Yes, if they liked to combine liquid intake along with carb intake

Anything further to say about the product in conclusion?

This is product does exactly what it sets out to do and therefore deserves a score of 9, but the price (although fair) isn't a bargain so gets a point knocked off, giving an overall score of 8.

Overall rating: 8/10

About the tester

Age: 53  Height: 5ft 10 / 178cm  Weight: 11 stone / 70kg

I usually ride: an old Marin Alp, an old steel classic  My best bike is: an old Giant Cadex (can you see a theme here?)

I've been riding for: Over 20 years  I ride: A few times a week  I would class myself as: Experienced

I regularly do the following types of riding: touring, club rides, sportives, general fitness riding, Trail riding and rough-stuff (off road on a road bike)


Add new comment


onecogmind | 9 years ago

Top tip: buy these from Waitrose. In my local store they sell these with a 3 for 2 offer for all vitamin and well-being products.

I have tried Torq and High 5 and others and these are the only gels I can stomach.

TheFatAndTheFurious | 9 years ago

More than one SiS gel in a day gives me a wracking headache for the rest of the day following a ride. No combination or amount of water/electrolyte/food seems to counter this.

However, I'm fine with CNP gels and my wife's brilliant banana/walnut loaf, so until the makeup of SiS changes substantially, I'm staying clear.

Would be interested if anyone else has similar experiences.

Acesulfame-K is NOT Aspartame. Granted, they are both artificial sweeteners not found in nature, but they are different chemical compounds.

Paul J | 9 years ago

£1.69 for 69g of maltodextrin. That's a *very* expensive way to buy something that's akin to glucose syrup in nutritional value. (Maltrodextrin has pretty much same calorific content, slightly faster absorbtion than glucose).

velocatso | 9 years ago

SIS gels are the only gels I can handle. They actually taste very nice compared to other brands, and don't upset my stomach - I always use them in conjunction with real food though. I couldn't imagine fuelling a long ride solely with gels.

noizebox | 9 years ago

Why on earth does this need sweeteners, and of all they could choose, why Aspartame?

maxfox replied to noizebox | 9 years ago
1 like

Cost, neutral chemical (won't mess up the gel structure), well established in the food market, metabolic constituents are not toxic.
I'd rather they used something more like stevia, but it is significantly more expensive.

maxfox replied to noizebox | 9 years ago
1 like

Cost, neutral chemical (won't mess up the gel structure), well established in the food market, metabolic constituents are not toxic.
I'd rather they used something more like stevia, but it is significantly more expensive.

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